vision

“Making Matrix for magazine for blind.” Photograph from glass negative, between ca. 1900 and ca. 1915. Image depicts a man at the New York Institute for the Blind using a Stereograph, a machine for embossing zinc plates with Braille, to use as publishing masters. George Grantham Bain Collection, Library of Congress, Prints and Photographs Division, Washington, D.C., USA.

For the upcoming GLIMPSE journalissue on the topic of Blindness, GLIMPSE correspondent Nadej Giroux has drafted a fascinating timeline of corrective technologies and innovations to address blindness.

We welcome your feedback and ideas (supported by citations, please!) on this draft.

The final version will be published in GLIMPSE issue #10, with a full bibliography and attribution to those who contribute!

Selected Dates in Vision:
Corrective Technologies and Innovations

ca.1286 — First glasses are created in Italy by the Dominican friar, Giordano da Pisa.

1508 – Leonardo da Vinci is first to introduce the concept of “contact lens” in his Codex of the eye, Manual D. Though none are produced at the time, the concept explored the idea of directly increasing corneal power of the eye.

1784 – Benjamin Franklin writes a letter to George Whatley, which describes his recent invention of “split double spectacles,” or bifocal lens glasses.

1786 – Valentin Haüy publishes a book titled An Essay on the Education of the Blind, in which he describes a process wherein the typographical characters used on a printing press would emboss letters upon the wet paper medium, thus creating a tactile font.

1823 – Creation of the first Fresnel lens, as attributed to Augustin-Jean Fresnel. Fresnel lenses are different from the regular spherical lens of a standard magnifying glass in that the former can be much thinner due to its structure, which is comprised of a set of thin raised concentric sections. As sight aids, Fresnel lens technology has been used to create flat magnification sheets that can be placed over a TV screen, helping to magnify the image.

1829 – Louis Braille publishes a book titled Method of Writing Words, Music and Plainsong by Means of Dots for Use by the Blind and Arranged for Them, exhibiting and explaining the original Braille type in French that is based on dots. More that half a century later, Braille type is introduced in Britain.

1837 – August Seebeck, classifies two distinct types of color blindness and is first suggest that the condition can be augmented with corrective lenses.

1851 – Hermann von Helmholtz invents the first ophthalmoscope, calling it an “eye mirror,” which is used to illuminate the interior of the eye behind the pupil.

1888 – Adolf Gaston Eugen Fick produces and fits the first successful pair of contact lenses. They are made of heavy blown glass with a dextrose solution inside. Although the original Fick lenses were a breakthrough, they were rather bulky and could only be worn for several hours at a time.

1949 – Sir Harold Ridley performs the first-ever successful implantation of intraocular lens, a procedure that many contemporary ophthalmologists considered impossible at the time.

1980s – Scanning Laser Opthalmoscope is developed to view microscopic layers of the retina of the living eye, and aids in diagnosing retinal disorders.

1999 – Professor Ingo Potrykus invents Golden Rice. This genetically engineered varietal was designed to contain beta carotene, which, when consumed is converted to vitamin A in the human body. Since vitamin A deficiency is linked to blindness, especially in the developing countries, the Golden Rice, along with Orange-fleshed sweet potato, are examples of biofortification tools that aim to prevent vision problems linked to VAD in the future.

2001 – ChromaGen lens human subjects study is published in Ophthalmic and Physiological Optics. The study used the ChromaGen brand color blindness corrective lenses in a two-week experiment that yielded positive subjective results in its wearers, among which were the significant reduction of Ishihara error rates, the later being the most common color blind test of circles and dots of varying sizes and with numbers represented in contrasting colors.

2002 – Argus Retinal Prosthesis is developed by Second Sight TM. This bionic eye project created a product that is a retinal prosthetic system, which induces visual acuity of blind patients by means of electrical stimulation to the retina, bypassing the damaged photoreceptors. With an aid of compact camera and video processing unit (VPU), the device “sends” the scene captured via camera though a cable to the VPU, to reconstruct the visual information for the Argus-II wearer. In September 2012, FDA recommended the approval of the second-generation Argus-II device, following several successful clinical trials in Europe, Mexico and United States.

2005 – Elizabeth Goldring, artist, poet, and head of the Vision Group at the Center for Advanced Visual Studies at the Massachusetts Institute of Technology, leads a team of engineers and physicians in the development and first clinical trials of the Seeing Machine Camera (SMC). The device uses liquid crystal display (LCD) and light-emitting diode (LED) technologies to affordably and portably replicate principles of the industrial-grade Scanning Laser Opthalmoscope. The SMC projects imagery directly onto the retina with highly-focused, bright light, avoiding the normal distortions and refractions of the impaired eye. The SMC allows people with a visual acuity of 20/70 or less to see things they would otherwise be unable to see (including small details of facial features), and to produce photographs of what they see.

2009 – Gene therapy is shown to successfully cure color blindness in two squirrel monkeys. The therapy worked by increasing the red end of the spectrum sensitivity of cone cells, effectively restoring color vision in the study’s subjects. The results of the study suggest further implication for treating human color blindness in the future.

2010 – First success with biosynthetic cornea transplantation procedures is reported by Fagerholm et al. of Linkoping University in Sweden. The development of the biosynthetic corneas rose out of shortage of donated corneas readily available for transplantation. The corneas in the Fagerholm’s lab were produced by injecting the human gene, responsible for collagen production into a type of yeast cells that were later molded into the corneal shape.

In anticipation of the forthcoming Glimpse issue on the theme of Blindness, we reflect on the societal contributions and civil rights of those born without, and those who have lost their eyesight, worldwide. Here in the United States, today, October 15, is Blind Americans Equality Day by resolution of the White House: “Today, let us recommit to ensuring we remain a Nation where all our people, including those with disabilities, have every opportunity to achieve their dreams.” We couldn’t agree more. Read the Full White House resolution below.

BLIND AMERICANS EQUALITY DAY, 2013
– – – – – – –
BY THE PRESIDENT OF THE UNITED STATES OF AMERICA
A PROCLAMATION

Blind and visually impaired persons have always played an important role in American life and culture, and today we recommit to our goals of full access and opportunity. Whether sprinting across finish lines, leading innovation in business and government, or creating powerful music and art, blind and visually impaired Americans imagine and pursue ideas and goals that move our country forward. As a Nation, it is our task to ensure they can always access the tools and support they need to turn those ideas and goals into realities.

My Administration is committed to advancing opportunity for people with disabilities through the Americans with Disabilities Act and other important avenues. In June of this year, the United States joined with over 150 countries in approving a landmark treaty that aims to expand access for visually impaired persons and other persons with print disabilities to information, culture, and education. By facilitating access to books and other printed material, the treaty holds the potential to open up worlds of knowledge. If the United States becomes a party to this treaty, we can reduce the book famine that confronts the blind community while maintaining the integrity of the international copyright framework.

The United States was also proud to join 141 other countries in signing the Convention on the Rights of Persons with Disabilities in 2009, and we are working toward its ratification. Americans with Disabilities, including those who are blind or visually impaired, should have the same opportunities to work, study, and travel in other countries as any other American, and the Convention can help us realize that goal.

To create a more level playing field and ensure students with disabilities have access to the general education curriculum, the Department of Education issued new guidance in June for the use of Braille as a literacy tool under the Individuals with Disabilities Education Act. This guidance reaffirms my Administration’s commitment to using Braille to open doors for students who are blind or visually impaired, so every student has a chance to succeed in the classroom and graduate from high school prepared for college and careers.

We have come a long way in our journey toward a more perfect Union, but we still have work ahead. We must fulfill the promise of life, liberty, and the pursuit of happiness and expand the freedom to make of our lives what we will. On this day, we celebrate the accomplishments of our blind and visually impaired citizens, and we recommit to building a Nation where all Americans, including those who are blind or visually impaired, live with the assurance of equal opportunity and equal respect.
By joint resolution approved on October 6, 1964 (Public Law 88-628, as amended), the Congress designated October 15 of each year as “White Cane Safety Day” to recognize the contributions of Americans who are blind or have low vision. Today, let us recommit to ensuring we remain a Nation where all our people, including those with disabilities, have every opportunity to achieve their dreams.

NOW, THEREFORE, I, BARACK OBAMA, President of the United States of America, by virtue of the authority vested in me by the Constitution and the laws of the United States, do hereby proclaim October 15, 2013, as Blind Americans Equality Day. I call upon public officials, business and community leaders, educators, librarians, and Americans across the country to observe this day with appropriate ceremonies, activities, and programs.

IN WITNESS WHEREOF, I have hereunto set my hand this eleventh day of October, in the year of our Lord two thousand thirteen, and of the Independence of the United States of America the two hundred and thirty-eighth.

You’ve probably heard the old adage about eating carrots for good vision. Well, there is some truth to it. Carrots contain a high concentration of β-carotene which gets broken down in the intestines to form the aldehyde (hydrocarbon) form of vitamin A, cis-retinal. Vision deteriorates in the absence of vitamin A because cis-retinal is trafficked along the protein, opsin, to produce electrochemical signals from light.

Our retinas perceive light in tiny particles called photons. As soon as these photons hit the retina, they isomerizecis-retinal to trans-retinal. Trans-retinal then bonds to opsin to form rhodopsin. Rhodopsin is a purple pigment in the photoreceptor cells of the retina that reads blue-green light. This is the first step of the phototransduction cycle where photon energy is transferred to a series of signaling and diffusing protein complexes.

Retinal isomerism drawn with ChemDraw

Mutated forms of rhodopsin will be folded and transported differently and could lead to deteriorated vision or blindness. In more rare cases, mutations can cause rhodopsin to be constantly activated, even in the absence of light. Hypersensitivity, autoimmune disorders, and mutations can all cause rod cells in the retina to undergo apoptosis or cellular self-destruction. This sort of degradation of the retina will ultimately lead to deteriorated vision and eventually blindness.

The absorbance of cis-retinal is optimized at approximately 100 nanometers less than rhodopsin and it is a very rigid molecule because of the arrangement of its double bonds. Thanks to isomerism, we can see in color as opposed to ultraviolet! As all of the above demonstrates, our ability to see involves a series of complicated and precisely regulated bio-chemical processes, and carrots play their role.

We will be exploring more about vision loss and blindness in the upcoming GLIMPSE issue 10, Blindness. In the meantime, let us know your thoughts, research, questions, or experiences related to the topic.

If you’re interested in the chemistry of vision and why we perceive the section of the electromagnetic spectrum that we do, you might also be interested in GLIMPSE, issue 4, Color, and the article on “Human Potential for Tetrachromacy” by Kimberley A. Jameson and the online supplementary article.

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Myya McGregory is the GLIMPSE 2012 Science Writing Intern. She is a junior double-majoring in chemistry and economics at Williams College. She enjoys music, dance, and literature.

If you follow science news you probably already know about the discovery of the Higgs boson particle. Having eluded scientists for years the so called “God particle” was detected in the Large Hadron Collider at CERN.

Unfortunately those who need to see it to believe it might be a little disappointed. Most heavy particles live fast and die young. The Higgs boson is no exception. It’s mass is between 115 and 158 GeV and it’s half life is less than a billionth of a second. Much like the famous yet elusive designer, Martin Margiela, the Higgs boson doesn’t want its picture taken.

Known as the God particle because its field is believed to give mass to every other particle before it decays, the Higgs boson is in fact omnipresent. We just can’t see it.

So how do we visualize the Higgs boson particle?

The short answer is: we don’t.

We do however see the effects of its energy and we can watch it decay. The Large Hadron Collider is basically a giant particle accelerator. When the particles hurdle towards each other and collide, they release energy and decay into lesser particles upon impact. As explained in CERN’s animation of their experiment, they hope to excite the Higgs field through the collision of two protons. At that time the Higgs boson will be present, but it will quickly decay into other standard model particles.

If you want a GLIMPSE of the experiment click through these pictures to see particles collide, and read more on CERN’s website here.

Like this:

As many of you will soon find out in the upcoming Cinema issue, persistence of vision is «the phenomenon of the eye by which an afterimage is thought to persist for approximately one twenty-fifth of a second on the retina». While the image is burned on the retina of the eye, we have time to send signals to the brain to identify the image.

Still from a flipbook created at the Museum of the Moving Image. Credit: Julia Rubinic

Persistence of vision, though thought to be a myth, could explain why our eyes perceive one continuous, moving image when we look at a progressions of stills.

This theory not only explains flipbooks but is also the basis of many film devices of the 19th century. The idea that images remain on the retina seconds after viewing means that images can be perceived as moving at speeds as low as 5 frames per second.

This also means that if an image vibrates fast enough, it can be perceived as static rather than kinetic.

Like this:

OK admit it: we all enjoy a little bit of gossip every now and then. Whether it be about a movie star or the next door neighbor, it piques our interest—especially if it happens to be negative. Perhaps a case of good old schadenfreude is the reason we take a guarded amusement in gossip, or maybe the simple fact that it’s more interesting to find out a person received a perfect score on a test through cheating rather than spending long hours at the library. But have we ever considered that hearing a juicy bit of gossip might actually be good for us? Researchers at Northeastern University concluded that people remember a face better when they hear negative gossip about a person than if they hear positive or neutral gossip, suggesting an evolutionary benefit to our guilty pleasure. The ability to easily spot a possible liar, cheat, or all-around bad person provides social protection; we wouldn’t want to spend time with people who might betray or deceive us. While that seems like an obvious statement, what makes this study fascinating is that it’s all happening at the unconscious level. Even if what we hear is untrue, it’s in our nature to be cautious.

Not only does the research give us a good excuse for our interest in gossip but it’s also a little reassuring. It reminds us that that we (excuse the pun) look out for ourselves. Our well-being is a priority, regardless of whether we realize it or not.